def test_size(self):
"""
Tests that the size of a linked list is returned
"""
l = LinkedList()
self.assertEqual(l.size(), 0)
l.insert_first(1)
l.insert_first(1)
l.insert_first(1)
l.insert_first(1)
self.assertEqual(l.size(), 4)
def test_clear(self):
"""
Test that a list is emptied
"""
l = LinkedList()
self.assertEqual(l.size(), 0)
l.insert_first(1)
l.insert_first(1)
l.insert_first(1)
l.insert_first(1)
self.assertEqual(l.size(), 4)
l.clear()
self.assertEqual(l.size(), 0)
def test_remove_first_size_3(self):
"""
Tests the removal of first node in list when list has three nodes
"""
l = LinkedList()
l.insert_first("c")
l.insert_first("b")
l.insert_first("a")
l.remove_first()
self.assertEqual(l.size(), 2)
self.assertEqual(l.get_first().data, "b")
l.remove_first()
self.assertEqual(l.size(), 1)
self.assertEqual(l.get_first().data, "c")
def test_insert_last(self):
"""
Tests adding a node to the end of a list
"""
l = LinkedList()
l.insert_first("a")
l.insert_last("b")
self.assertEqual(l.size(), 2)
self.assertEqual(l.get_last().data, "b")
def test_remove_first_size_1(self):
"""
Tests the removal of first node in list when list has one node
"""
l = LinkedList()
l.insert_first("a")
l.remove_first()
self.assertEqual(l.size(), 0)
self.assertEqual(l.get_first(), None)
def test_remove_last_3(self):
"""
Tests the removal of last node in a list with three nodes
"""
l = LinkedList()
l.insert_first("c")
l.insert_first("b")
l.insert_first("a")
l.remove_last()
self.assertEqual(l.size(), 2)
self.assertEqual(l.get_last().data, "b")
def test_remove_last_2(self):
"""
Tests the removal of last node in a list with two nodes
"""
l = LinkedList()
l.insert_first("b")
l.insert_first("a")
l.remove_last()
self.assertEqual(l.size(), 1)
self.assertEqual(l.get_last().data, "a")
self.assertEqual(l.get_last().next, None)